I did something similar in a tunnel like that years ago with my 76 Chevy Monte Carlo with a 454 big block engine with dual headers and dual glass pack exhaust. It was super loud and mean sounding and i used to go in the downtown tunnel in FL and put my car in neutral and Rev my loud 454 in that tunnel and make almost everyone pull over and stop inside the tunnel and the people walking at the light downtown would look everywhere and duck scared and run like they think the worlds gonna end. LMAO!